How to get current post_id in function.php file

Question

This is my function in function.php file

  function getcity(){
    global $wpdb;

    if($_POST[\'state\'])
            {
                $id=$_POST[\'state\         


        

Answer 1

You want the global variable $post as documented here:

http://codex.wordpress.org/Global_Variables

Declare the $post global like so:

global $post;

Then you should be able to access the id of the post using $post->ID.

Here is a more complete doc of the attributes available through the $post global: http://codex.wordpress.org/Function_Reference/$post